package mt

import (
	"crypto/sha1"
	"fmt"
	"image/color"
	"io"
	"math"

	"github.com/HimbeerserverDE/mt/rudp"
)

type ToCltCmd interface {
	Cmd
	toCltCmdNo() uint16
}

//go:generate ./cmdno.sh tocltcmds ToClt toClt uint16 Cmd newToCltCmd

// ToCltHello is sent as a response to ToSrvInit.
// The client responds to ToCltHello by authenticating.
type ToCltHello struct {
	SerializeVer uint8
	Compression  CompressionModes
	ProtoVer     uint16
	AuthMethods
	Username string
}

// ToCltAcceptAuth is sent after the client successfully authenticates.
// The client responds to ToCltAcceptAuth with ToSrvInit2.
type ToCltAcceptAuth struct {
	// The client does the equivalent of
	//	PlayerPos[1] -= 5
	// before using PlayerPos.
	PlayerPos Pos

	MapSeed         uint64
	SendInterval    float32
	SudoAuthMethods AuthMethods
}

type ToCltAcceptSudoMode struct {
	SudoAuthMethods AuthMethods
	//mt:const [15]byte{}
}

type ToCltDenySudoMode struct{}

// ToCltKick tells that the client that it has been kicked by the server.
type ToCltKick struct {
	Reason KickReason
	//mt:assert %s.Reason < maxKickReason

	//mt:if dr := %s.Reason; dr == Custom || dr == Shutdown || dr == Crash
	Custom string
	//mt:end

	//mt:if dr := %s.Reason; dr == Shutdown || dr == Crash
	Reconnect bool
	//mt:end
}

// A KickReason is the reason a ToCltKick has been sent.
type KickReason uint8

const (
	WrongPasswd KickReason = iota
	UnexpectedData
	SrvIsSingleplayer
	UnsupportedVer
	BadNameChars
	BadName
	TooManyClts
	EmptyPasswd
	AlreadyConnected
	SrvErr
	Custom
	Shutdown
	Crash
	maxKickReason
)

func (cmd ToCltKick) String() (msg string) {
	switch cmd.Reason {
	case WrongPasswd:
		return "wrong password"
	case UnexpectedData:
		return "unexpected data"
	case SrvIsSingleplayer:
		return "server is singleplayer"
	case UnsupportedVer:
		return "unsupported client version"
	case BadNameChars:
		return "disallowed character(s) in player name"
	case BadName:
		return "disallowed player name"
	case TooManyClts:
		return "too many clients"
	case EmptyPasswd:
		return "empty password"
	case AlreadyConnected:
		return "another client is already connected with the same name"
	case SrvErr:
		return "server error"
	case Custom:
		return cmd.Custom
	case Shutdown:
		msg = "server shutdown"
	case Crash:
		msg = "server crash"
	default:
		msg = fmt.Sprintf("KickReason(%d)", cmd.Reason)
	}

	if cmd.Custom != "" {
		msg += ": " + cmd.Custom
	}

	return
}

// ToCltBlkData tells the client the contents of a nearby MapBlk.
type ToCltBlkData struct {
	Blkpos [3]int16
	//mt:zstd
	Blk MapBlk
	//mt:end
}

// ToCltAddNode tells the client that a nearby node changed
// to something other than air.
type ToCltAddNode struct {
	Pos [3]int16
	Node
	KeepMeta bool
}

// ToCltRemoveNode tells the client that a nearby node changed to air.
type ToCltRemoveNode struct {
	Pos [3]int16
}

// ToCltInv updates the client's inventory.
type ToCltInv struct {
	//mt:raw
	Inv string
}

// ToCltTimeOfDay updates the client's in-game time of day.
type ToCltTimeOfDay struct {
	Time  uint16  // %24000
	Speed float32 // Speed times faster than real time
}

// ToCltCSMRestrictionFlags tells the client how use of CSMs should be restricted.
type ToCltCSMRestrictionFlags struct {
	Flags CSMRestrictionFlags

	// MapRange is the maximum distance from the player CSMs can read the map
	// if Flags&LimitMapRange != 0.
	MapRange uint32
}

type CSMRestrictionFlags uint64

const (
	NoCSMs CSMRestrictionFlags = 1 << iota
	NoChatMsgs
	NoItemDefs
	NoNodeDefs
	LimitMapRange
	NoPlayerList
)

// ToCltAddPlayerVel tells the client to add Vel to the player's velocity.
type ToCltAddPlayerVel struct {
	Vel Vec
}

// ToCltMediaPush is sent when a media file is dynamically added.
type ToCltMediaPush struct {
	//mt:const uint16(sha1.Size)
	SHA1          [sha1.Size]byte
	Filename      string
	Ephemeral     bool
	CallbackToken uint32
}

// ToCltChatMsg tells the client that is has received a chat message.
type ToCltChatMsg struct {
	//mt:const uint8(1)

	Type ChatMsgType

	//mt:utf16
	Sender, Text string

	Timestamp int64 // Unix time.
}

type ChatMsgType uint8

const (
	RawMsg      ChatMsgType = iota // raw
	NormalMsg                      // normal
	AnnounceMsg                    // announce
	SysMsg                         // sys
	maxMsg
)

//go:generate stringer -linecomment -type ChatMsgType

// ToCltAORmAdd tells the client that AOs have been removed from and/or added to
// the AOs that it can see.
type ToCltAORmAdd struct {
	Remove []AOID
	Add    []AOAdd
}

type AOAdd struct {
	ID AOID
	//mt:const genericCAO
	//mt:lenhdr 32
	InitData AOInitData
	//mt:end
}

// ToCltAOMsgs updates the client about nearby AOs.
type ToCltAOMsgs struct {
	//mt:raw
	Msgs []IDAOMsg
}

// ToCltHP updates the player's HP on the client.
type ToCltHP struct {
	HP           uint16
	DamageEffect bool
}

// ToCltMovePlayer tells the client that the player has been moved server-side.
type ToCltMovePlayer struct {
	Pos
	Pitch, Yaw float32
}

type ToCltLegacyKick struct {
	//mt:utf16
	Reason string
}

// ToCltFOV tells the client to change its FOV.
type ToCltFOV struct {
	FOV            float32
	Multiplier     bool
	TransitionTime float32
}

// ToCltDeathScreen tells the client to show the death screen.
type ToCltDeathScreen struct {
	PointCam bool
	PointAt  Pos
}

// ToCltMedia responds to a ToSrvMedia packet with the requested media files.
type ToCltMedia struct {
	// N is the total number of ToCltMedia packets.
	// I is the index of this packet.
	N, I uint16

	//mt:len32
	Files []struct {
		Name string

		//mt:len32
		Data []byte
	}
}

// ToCltNodeDefs tells the client the definitions of nodes.
type ToCltNodeDefs struct {
	//mt:lenhdr 32
	//mt:zlib

	// Version.
	//mt:const uint8(1)

	// See (de)serialize.fmt.
	Defs []NodeDef

	//mt:end
	//mt:end
}

// ToCltAnnounceMedia tells the client what media is available on request.
// See ToSrvReqMedia.
type ToCltAnnounceMedia struct {
	Files []struct {
		Name       string
		Base64SHA1 string
	}
	URL string
}

// ToCltItemDefs tells the client the definitions of items.
type ToCltItemDefs struct {
	//mt:lenhdr 32
	//mt:zlib

	//mt:const uint8(0)

	Defs    []ItemDef
	Aliases []struct{ Alias, Orig string }

	//mt:end
	//mt:end
}

// ToCltPlaySound tells the client to play a sound.
type ToCltPlaySound struct {
	ID      SoundID
	Name    string
	Gain    float32
	SrcType SoundSrcType
	Pos
	SrcAOID   AOID
	Loop      bool
	Fade      float32
	Pitch     float32
	Ephemeral bool
	StartTime float32
}

// ToCltStopSound tells the client to stop playing a sound.
type ToCltStopSound struct {
	ID SoundID
}

// ToCltPrivs tells the client its privs.
type ToCltPrivs struct {
	Privs []string
}

// ToCltInvFormspec tells the client its inventory formspec.
type ToCltInvFormspec struct {
	//mt:len32
	Formspec string
}

// ToCltDetachedInv updates a detached inventory on the client.
type ToCltDetachedInv struct {
	Name string
	Keep bool
	Len  uint16 // deprecated

	//mt:raw
	Inv string
}

// ToCltShowFormspec tells the client to show a formspec.
type ToCltShowFormspec struct {
	//mt:len32
	Formspec string

	Formname string
}

// ToCltMovement tells the client how to move.
type ToCltMovement struct {
	DefaultAccel, AirAccel, FastAccel,
	WalkSpeed, CrouchSpeed, FastSpeed, ClimbSpeed, JumpSpeed,
	Fluidity, Smoothing, Sink, // liquids
	Gravity float32
}

// ToCltSpawnParticle tells the client to spawn a particle.
type ToCltSpawnParticle struct {
	Pos, Vel, Acc  [3]float32
	ExpirationTime float32 // in seconds.
	Size           float32
	Collide        bool

	//mt:len32
	TextureName Texture

	Vertical    bool
	CollisionRm bool
	AnimParams  TileAnim
	Glow        uint8
	AOCollision bool
	NodeParam0  Content
	NodeParam2  uint8
	NodeTile    uint8
	Drag        [3]float32
	Jitter      RangeV3F32
	Bounce      RangeF32
	Texture     ParticleTexture
}

type ParticleSpawnerID uint32

// ToCltAddParticleSpawner tells the client to add a particle spawner.
type ToCltAddParticleSpawner struct {
	Amount         uint16
	Duration       float32
	Pos, Vel, Acc  TweenRangeV3F32
	ExpirationTime TweenRangeF32 // in seconds.
	Size           TweenRangeF32
	Collide        bool

	//mt:len32
	TextureName Texture

	ID           ParticleSpawnerID
	Vertical     bool
	CollisionRm  bool
	AttachedAOID AOID
	AnimParams   TileAnim
	Glow         uint8
	AOCollision  bool

	NodeParam0 Content
	NodeParam2 uint8
	NodeTile   uint8

	Texture ParticleTexture

	Drag   TweenRangeV3F32
	Jitter TweenRangeV3F32
	Bounce TweenRangeF32

	Attraction AttractionKind

	//mt:if %s.Attraction != NoAttraction
	AttractStrength           TweenRangeF32
	AttractorOrigin           TweenV3F32
	AttractorOriginAttachedAO AOID
	Flags                     ParticleSpawnerFlags

	//mt:if %s.Attraction != PointAttraction
	AttractorAngle           TweenV3F32
	AttractorAngleAttachedAO AOID
	//mt:end
	//mt:end

	Radius TweenRangeV3F32

	//mt:len16
	Textures []ParticleTexture
}

type HUD struct {
	Type HUDType

	Pos      [2]float32
	Name     string
	Scale    [2]float32
	Text     string
	Number   uint32
	Item     uint32
	Dir      uint32
	Align    [2]float32
	Offset   [2]float32
	WorldPos Pos
	Size     [2]int32
	ZIndex   int16
	Text2    string
	Style    HUDStyleFlags
}

type HUDID uint32

// ToCltHUDAdd tells the client to add a HUD.
type ToCltAddHUD struct {
	ID HUDID
	HUD
}

type HUDType uint8

const (
	ImgHUD HUDType = iota
	TextHUD
	StatbarHUD
	InvHUD
	WaypointHUD
	ImgWaypointHUD
)

//go:generate stringer -type HUDType

// ToCltRmHUD tells the client to remove a HUD.
type ToCltRmHUD struct {
	ID HUDID
}

// ToCltChangeHUD tells the client to change a field in a HUD.
type ToCltChangeHUD struct {
	ID HUDID

	Field HUDField

	//mt:assert %s.Field < hudMax

	//mt:if %s.Field == HUDPos
	Pos [2]float32
	//mt:end

	//mt:if %s.Field == HUDName
	Name string
	//mt:end

	//mt:if %s.Field == HUDScale
	Scale [2]float32
	//mt:end

	//mt:if %s.Field == HUDText
	Text string
	//mt:end

	//mt:if %s.Field == HUDNumber
	Number uint32
	//mt:end

	//mt:if %s.Field == HUDItem
	Item uint32
	//mt:end

	//mt:if %s.Field == HUDDir
	Dir uint32
	//mt:end

	//mt:if %s.Field == HUDAlign
	Align [2]float32
	//mt:end

	//mt:if %s.Field == HUDOffset
	Offset [2]float32
	//mt:end

	//mt:if %s.Field == HUDWorldPos
	WorldPos Pos
	//mt:end

	//mt:if %s.Field == HUDSize
	Size [2]int32
	//mt:end

	//mt:if %s.Field == HUDZIndex
	ZIndex int32
	//mt:end

	//mt:if %s.Field == HUDText2
	Text2 string
	//mt:end

	//mt:if %s.Field == HUDStyle
	Style HUDStyleFlags
	//mt:end
}

type HUDField uint8

const (
	HUDPos HUDField = iota
	HUDName
	HUDScale
	HUDText
	HUDNumber
	HUDItem
	HUDDir
	HUDAlign
	HUDOffset
	HUDWorldPos
	HUDSize
	HUDZIndex
	HUDText2
	HUDStyle
	hudMax
)

//go:generate stringer -trimprefix HUD -type HUDField

type HUDStyleFlags uint32

const (
	StyleBold HUDStyleFlags = 1 << iota
	StyleItalic
	StyleMono
)

//go:generate stringer -trimprefix Style -type HUDStyleFlags

// ToCltHUDFlags tells the client to update its HUD flags.
type ToCltHUDFlags struct {
	// &^= Mask
	// |= Flags
	Flags, Mask HUDFlags
}

type HUDFlags uint32

const (
	ShowHotbar HUDFlags = 1 << iota
	ShowHealthBar
	ShowCrosshair
	ShowWieldedItem
	ShowBreathBar
	ShowMinimap
	ShowRadarMinimap
)

// ToCltSetHotbarParam tells the client to set a hotbar parameter.
type ToCltSetHotbarParam struct {
	Param HotbarParam

	//mt:if %s.Param == HotbarSize
	//mt:const uint16(4) // Size of Size field.
	Size int32
	//mt:end

	//mt:if %s.Param != HotbarSize
	Img Texture
	//mt:end
}

type HotbarParam uint16

const (
	HotbarSize HotbarParam = 1 + iota
	HotbarImg
	HotbarSelImg
)

//go:generate stringer -trimprefix Hotbar -type HotbarParam

// ToCltBreath tells the client how much breath it has.
type ToCltBreath struct {
	Breath uint16
}

// ToCltSkyParams tells the client how to render the sky.
type ToCltSkyParams struct {
	BgColor     color.NRGBA
	Type        string
	Clouds      bool
	SunFogTint  color.NRGBA
	MoonFogTint color.NRGBA
	FogTintType string

	//mt:if %s.Type == "skybox"
	Textures []Texture
	//mt:end

	//mt:if %s.Type == "regular"
	DaySky, DayHorizon,
	DawnSky, DawnHorizon,
	NightSky, NightHorizon,
	Indoor color.NRGBA
	//mt:end

	BodyOrbitTilt float32

	FogDistance int16
	FogStart    float32
	FogColor    color.NRGBA
}

// ToCltOverrideDayNightRatio overrides the client's day-night ratio
type ToCltOverrideDayNightRatio struct {
	Override bool
	Ratio    uint16
}

// ToCltLocalPlayerAnim tells the client how to animate the player.
type ToCltLocalPlayerAnim struct {
	Idle, Walk, Dig, WalkDig [2]int32
	Speed                    float32
}

// ToCltEyeOffset tells the client where to position the camera
// relative to the player.
type ToCltEyeOffset struct {
	First, Third, ThirdFront Vec
}

// ToCltDelParticleSpawner tells the client to delete a particle spawner.
type ToCltDelParticleSpawner struct {
	ID ParticleSpawnerID
}

// ToCltCloudParams tells the client how to render the clouds.
type ToCltCloudParams struct {
	Density      float32
	DiffuseColor color.NRGBA
	AmbientColor color.NRGBA
	ShadowColor  color.NRGBA
	Height       float32
	Thickness    float32
	Speed        [2]float32
}

// ToCltFadeSound tells the client to fade a sound.
type ToCltFadeSound struct {
	ID   SoundID
	Step float32
	Gain float32
}

// ToCltUpdatePlayerList informs the client of players leaving or joining.
type ToCltUpdatePlayerList struct {
	Type    PlayerListUpdateType
	Players []string
}

type PlayerListUpdateType uint8

const (
	InitPlayers   PlayerListUpdateType = iota // init
	AddPlayers                                // add
	RemovePlayers                             // remove
)

//go:generate stringer -linecomment -type PlayerListUpdateType

// ToCltModChanMsg tells the client it has been sent a message on a mod channel.
type ToCltModChanMsg struct {
	Channel string
	Sender  string
	Msg     string
}

// ToCltModChanSig tells the client it has received a signal on a mod channel.
type ToCltModChanSig struct {
	Signal  ModChanSig
	Channel string
}

type ModChanSig uint8

const (
	JoinOK ModChanSig = iota
	JoinFail
	LeaveOK
	LeaveFail
	NotRegistered
	SetState
)

//go:generate stringer -type ModChanSig

// ToCltNodeMetasChanged is sent when node metadata near the client changes.
type ToCltNodeMetasChanged struct {
	//mt:lenhdr 32
	Changed map[[3]int16]*NodeMeta
	//mt:end
}

// ToCltSunParams tells the client how to render the sun.
type ToCltSunParams struct {
	Visible bool
	Texture
	ToneMap Texture
	Rise    Texture
	Rising  bool
	Size    float32
}

// ToCltMoonParams tells the client how to render the moon.
type ToCltMoonParams struct {
	Visible bool
	Texture
	ToneMap Texture
	Size    float32
}

// ToCltStarParams tells the client how to render the stars.
type ToCltStarParams struct {
	Visible    bool
	Count      uint32
	Color      color.NRGBA
	Size       float32
	DayOpacity float32
}

// ToCltMovePlayerRel tells the client that the player has been moved
// server-side by a relative offset.
type ToCltMovePlayerRel struct {
	Pos
}

type ToCltSRPBytesSaltB struct {
	Salt, B []byte
}

// ToCltFormspecPrepend tells the client to prepend a string to all formspecs.
type ToCltFormspecPrepend struct {
	Prepend string
}

// ToCltMinimapModes tells the client the set of available minimap modes.
type ToCltMinimapModes struct {
	Current uint16
	Modes   []MinimapMode
}

var _ serializer = (*ToCltMinimapModes)(nil)

func (cmd *ToCltMinimapModes) serialize(w io.Writer) {
	buf := make([]byte, 4)
	if len(cmd.Modes) > math.MaxUint16 {
		chk(ErrTooLong)
	}
	be.PutUint16(buf[0:2], uint16(len(cmd.Modes)))
	be.PutUint16(buf[2:4], cmd.Current)
	_, err := w.Write(buf)
	chk(err)
	for i := range cmd.Modes {
		chk(serialize(w, &cmd.Modes[i]))
	}
}

var _ deserializer = (*ToCltMinimapModes)(nil)

func (cmd *ToCltMinimapModes) deserialize(r io.Reader) {
	buf := make([]byte, 4)
	_, err := io.ReadFull(r, buf)
	chk(err)
	cmd.Modes = make([]MinimapMode, be.Uint16(buf[0:2]))
	cmd.Current = be.Uint16(buf[2:4])
	for i := range cmd.Modes {
		chk(deserialize(r, &cmd.Modes[i]))
	}
}

// ToCltLighting tells the client the shadow intensity of the local player.
type ToCltLighting struct {
	ShadowIntensity    float32
	Saturation         float32
	LuminanceMin       float32
	LuminanceMax       float32
	ExposureCorrection float32
	SpeedDarkBright    float32
	SpeedBrightDark    float32
	CenterWeightPower  float32
	VolumetricStrength float32
	ShadowTint         color.NRGBA
	BloomIntensity     float32
	BloomStrength      float32
	BloomRadius        float32
}

type ToCltDisco struct{}

func (*ToCltDisco) cmd()                         {}
func (*ToCltDisco) toCltCmdNo() uint16           { return 0xffff }
func (*ToCltDisco) DefaultPktInfo() rudp.PktInfo { return rudp.PktInfo{} }